Abstract: A surface wave device (SWD) programmable to produce any one of a plurality of phase coded SWD digital delay line configurations from a single transducer pattern characterized by parallel transducer electrode arrays to provide for each of two opposite phase alternatives of acoustic surface waves being propagated. Each transducer comprises pairs of interdigital taps, each tap characterizing a single binary bit. Transducer phase coding is accomplished by severing in selected taps all metalized fingers of like polarity from their common conductor bar. Critical configuration tolerances prohibitive to programmed operations are thus obviated.

Abstract: An SWD structure is employed in an FM receiver for signal demodulation and band limiting. An FM signal is applied to the input of an SWD patterned for bandwidth limitation. Two SWD output channels characterized by predetermined differential delays of the modulated input signal are amplitude limited and mixed to produce an audio modulation component.